Airless spray equipment such as airless paint sprayers is customarily employed in many painting applications. According to conventional airless spraying techniques, the paint or other fluid is maintained in the airless spray equipment under very high hydraulic pressure; this equipment on actuation typically produces spray at from about one to four thousand psi. Airless spray equipment, particularly the manually operated equipment such as airless spray guns, is thus inherently hazardous, as the paint spray in close proximity to the skin of the operator may cause injury to the skin, and further, the highly pressurized spray is capable of penetrating exposed portions of the body, thereby injecting paint into the body.
In order to minimize these hazards, numerous safety mechanisms for use in conjunction with such equipment have been proposed. Typically, these safety mechanisms have the disadvantage of requiring manual operation to inactivate the spray equipment, and the efficacy of such safety mechanisms is therefore determined by the conscientiousness of the equipment operator and limited to non-emergency situations. While automatic safety mechanisms, such as that described in U.S. Pat. No. 3,913,844 to Petrovic, are also known in the prior art, mechanisms such as those described by Petrovic are limited in their application to specific circumstances, for example, automatic disablement of the spray equipment when the equipment is dismantled for cleaning.
Accordingly, it is an object of the present invention to provide an automatic safety mechanism for airless spray equipment which substantially minimizes the hazards associated with the use of such equipment.
It is another object of this invention to provide a safety mechanism for manually-operated airless spray equipment such as airless spray guns which is automatically activated on full release of the spray equipment actuating mechanism.
It is an additional object of this invention to provide a safety mechanism for airless spray equipment such as airless spray guns which automatically functions to prevent accidental operation of the spray equipment actuating mechanism, but which can be readily counteracted by the equipment operator.